Histone deacetylase (HDAC) (Class I and II) (HDAC (Class I/II))

Histone deacetylases (HDACs) are enzymes responsible for the removal of acetyl groups from the lysine residues of both histone and non-histone proteins (UniProt: HDAC1, 2023) [3]. Class I and II HDACs play a pivotal role in epigenetic regulation by modulating chromatin architecture; their activity typically promotes a condensed chromatin state that represses gene transcription (StatPearls: Vorinostat, 2023) [1]. In various malignancies, these enzymes are often dysregulated, leading to the silencing of genes involved in cell cycle control and apoptosis (Journal of Hematology & Oncology, 2012) [4]. Vorinostat is a hydroxamic acid-based small molecule that serves as a potent inhibitor of Class I and II HDACs (PubChem: Vorinostat, 2024) [2]. By chelating the zinc ion within the enzyme's active site, vorinostat prevents deacetylation, resulting in the accumulation of acetylated histones and the reactivation of tumor suppressor genes, ultimately inducing growth arrest and cell death in cancer cells (NCI Drug Dictionary) [5]. Beyond oncology, Class I and II HDACs are being investigated as therapeutic targets for inflammatory and neurodegenerative conditions due to their broad impact on cellular signaling and protein stability (PubMed: HDAC inhibitors in disease, 2021) [6].

Other names

Histone deacetylasesHDACsLysine deacetylasesKDACsClass I HDACsClass II HDACs

Vorinostat inhibits the enzymatic activity of Class I and II histone deacetylases by binding to the zinc ion located in the catalytic pocket of the enzyme (StatPearls: Vorinostat, 2023) [1]. This inhibition prevents the removal of acetyl groups from lysine residues on histones and non-histone proteins, leading to hyperacetylation, altered gene expression, and induction of apoptosis (PubChem: Vorinostat, 2024) [2].